Xamarin gets IP -- meaning they don't have to do a clean-room, source-compatible reimplementation of MonoTouch and Mono for Android, and all the risks that go with that -- in exchange for taking on the support of Novell's existing customers. Customers they probably want anyway.
Novell/SUSE gets to get out of the Mono business altogether, which is probably good for them seeing as they laid off the entire engineering staff.
The Mono community gets some clarification about the stewardship of the project. Novell contributed a lot of resources (bug tracker, mailing list and wiki hosting, etc.) and now Xamarin is on the hook for that stuff. It helps clarify the future of the project.